> all their music, movies, apps, etc are in Apple's DRM format and won't transfer to other devices.
Music on iOS devices isn't DRMed and hasn't been for some time. If your new device can't play m4a files this is a separate issue and you can transcode them just like if you had a pile of drm-free WMAs.
Apps are DRMed but even if they weren't it'd be irrelevant unless a WINE-analogue for iOS came about (and consider the time-scale this would take and performance issues, etc. UIKit is non-trivial). I can't move an Android app onto my iPhone either, despite its lack of DRM, and whether the blocker is legal or technical is irrelevant. The real problem isn't that a user can't move their 99c iOS whatever-app to their new android phone, it's that they can't find or don't know how to find or can't be bothered finding equivalent app(s) for their new phone. Leaving aside the whole question of relative top-tier application quality on the platforms.
Movies, I don't know the behaviour here. Do people collect big libraries of apple DRM-ed movies, enough to keep them stuck to a phone? TV episodes I could see, but those strike me as more disposable in any case.
What is the 'etc' in "music, movies, apps, etc"? It's not your photos. It's not your emails. It's not your calendars or your contacts. It's not even the data saved in your applications - there's a trivial API now for transferring files from an application to your desktop via iTunes; if you can't export the data from your favourite applications to transfer to a different platform, that's on the application developers, not Apple.
I suppose it could be your alarms, preferred weather cities and stocks app choices. Or your SMS database, which I bet most people don't even consider as something that should easily transfer from phone to phone (though obviously it should).